Impact of seaweeds extracts applied to grapevine cv Tempranillo

Making high quality but affordable Pinot noir (PN) wine is challenging in most terroirs and New Zealand’s (NZ) situation is no exception. To increase the probability of making highly typical PN wines producers choose to grow grapes in cool climates on lower fertility soils while adopting labour intensive practices. Stringent yield targets and higher input costs necessarily mean that PN wine cost is high, and profitability lower, in line-priced varietal wine ranges. To understand the reasons why higher yielding vines are perceived to produce wines of lower quality we have undertaken an extensive study of PN in NZ. Since 2018, we established a network of twelve trial sites in three NZ regions to find individual vines that produced acceptable commercial yields (above 2.5kg per vine) and wines of composition comparable to “Icon” labels. Approximately 20% of 660 grape lots (N = 135) were selected from within a narrow juice Total Soluble Solids (TSS) range and made into single vine wines under controlled conditions. Principal Component Analysis of the vine, berry, juice and wine parameters from three vintages found grape berry mass to be most effective clustering variable. As berry mass category decreased there was a systematic increase in the probability of higher berry red colour and total phenolics with a parallel increase in wine phenolics, changed aroma fraction and decreased juice amino acids. The influence of berry size on wine composition would appear stronger than the individual effects of vintage, region, vineyard or vine yield. Our observations support the hypothesis that it is possible to produce PN wines that fall within an “Icon” benchmark composition range at yields above 2.5kg per vine provided that the Leaf Area:Fruit Weight ratio is above 12cm2 per g, mean berry mass is below 1.2g and juice TSS is above 22°Brix.

AIM. Wine yeast lees constitute a winemaking by-product that, unlike grape skins and seeds, are not sufficiently exploited to add value to the winemaking sector, as their treatment and disposal generally represents a cost for wineries [1].

AIM: Wine consumption in the last fifteen years showed a decrease in Europe [1]. New alternatives of wines appeared on the market. Those beverages are obtained by blending wines and fruit juices or flavoring wines with artificial or natural aromas and have medium alcohol content (from 8 to 10.5%) [2]. Recently, an innovative fruit wine has been proposed obtained by co-fermenting grape must and kiwi juice [3] whose potential attractiveness to consumers should be exploited. However, differences in product acceptability and perception, as well as the individuals’ willingness to consume and pay could change in function of subjects socio-demographic characteristics. The target group selected is represented by young adults (18-35 years old) consumption groups.

Herbicides are commonly sprayed in the vine row to prevent competition with vines for water and minerals and to keep weeds from growing into the bunch zone. Sprays are applied before budbreak and reapplied multiple times during the season to keep the undervine bare. There is growing concern about the negative effects of herbicides on humans and the environment, and weeds in New Zealand have developed resistance to herbicides. Therefore, it is imperative that we reduce our reliance on herbicides in viticulture and incorporate methods that do not engender resistance.

The knowledge about the molecular fraction associated to white wines oxidative stability is still poorly understood.